TOPEX/POSEIDON Altimeter Sea Surface Height Anomaly (SSHA)

Brief description

This dataset has the along-track sea surface height anomalies (SSHA) for the TOPEX/Poseidon mission up to the time of its orbit change (September, 1992 - August, 2002; cycles 1-365). The data from after the orbit change (September, 2002 - September, 2005) are available elsewhere. The dual-frequency NASA radar altimeter, NRA, is the primary instrument of the TOPEX/Poseidon mission. It works by sending radio pulses at 13.6 GHz and 5.3 GHz toward the earth and measuring the characteristics of the echo. By combining this measurement with data from the microwave radiometer and with other information from the spacecraft and the ground, scientists can calculate the height of the sea surface to within 4.3 centimeters. The data have been corrected for "path delay" effects (wet- and dry-troposphere, ionosphere, sea-state bias), for tides, and for the inverse barometer effect.